Gastrointestinal Cancers
Gastrointestinal (GI) cancers are a group of malignant conditions that affect the organs of the digestive system. This includes cancers of the oesophagus, stomach, liver, pancreas, small intestine, colon (large intestine), rectum, and anus. These cancers can be particularly challenging to diagnose and treat, as they often do not cause noticeable symptoms in their early stages.
Key Risk Factors
Risk factors for GI cancers vary depending on the specific organ affected, but there are some common contributing factors.
Dietary Habits: A diet low in fruits and vegetables and high in red and processed meats, salted, or smoked foods is a significant risk factor, especially for stomach and colorectal cancers.
Lifestyle Choices: Smoking and excessive alcohol consumption are strongly linked to an increased risk of several GI cancers, particularly those of the oesophagus, stomach, and liver. Obesity and a sedentary lifestyle also contribute to the risk of many GI cancers.
Infections: Chronic infections can be a major cause. For example, Helicobacter pylori (H. pylori) infection is a primary risk factor for stomach cancer, while chronic hepatitis B or C viral infections are the leading cause of liver cancer.
Age and Genetics: The risk of most GI cancers increases with age. A family history of GI cancers and inherited genetic syndromes, such as Lynch syndrome or familial adenomatous polyposis, can also significantly increase a person's risk.
Pre-existing Conditions: Certain non-cancerous conditions can lead to cancer. Examples include chronic gastritis (inflammation of the stomach), gastroesophageal reflux disease (GERD), and liver cirrhosis.
Epidemiology
In India, the burden of gastrointestinal cancers is considerable, and the epidemiology shows significant regional variations.
Overall Burden: GI cancers are a major public health issue in India. While breast and cervical cancers are the most common among women, certain GI cancers are prevalent, particularly among men.
Regional Differences: The incidence of GI cancers varies widely across the country. The Northeast region of India, including states like Mizoram and Sikkim, has some of the highest rates of oesophageal and stomach cancers in the world. This is often linked to traditional dietary practices, such as the consumption of smoked and fermented foods, and the use of tobacco and betel nut.
Rising Incidence: While some types of GI cancer, like stomach cancer, have seen a declining trend in some parts of India, cancers of the colon, rectum, and liver are on the rise, especially in urban areas. This is likely due to changing lifestyles, including dietary shifts and reduced physical activity, mirroring trends seen in Western countries.
Typical Symptoms
The symptoms of GI cancers are often nonspecific and can be confused with those of other, less serious conditions. They also depend on the specific location of the tumour. It is crucial to consult a doctor if any of these symptoms persist.
Oesophageal Cancer: Difficulty swallowing (dysphagia), a sensation of food getting stuck in the throat, chest pain, and unintentional weight loss.
Stomach Cancer: Indigestion, heartburn, feeling bloated after eating small amounts of food, nausea, and abdominal pain.
Colorectal Cancer: A change in bowel habits (e.g., diarrhoea or constipation), blood in the stool, a constant feeling of needing to have a bowel movement, and unexplained weight loss or fatigue.
Liver Cancer: Abdominal pain, a mass in the upper abdomen, jaundice (yellowing of the skin and eyes), and unexplained weight loss.
Pancreatic Cancer: Abdominal pain that radiates to the back, jaundice, weight loss, and new-onset diabetes.
Treatment
Treatment for GI cancers is highly individualised and depends on the type, stage, and location of the tumour, as well as the patient's overall health. A multi-modal approach is often used, combining several therapies.
Surgery: This is a primary treatment for many GI cancers, especially in the early stages. The goal is to surgically remove the tumour and a margin of healthy tissue. Depending on the cancer's location, this could be a partial or total removal of the affected organ, along with nearby lymph nodes.
Chemotherapy: The use of drugs to kill cancer cells. It can be given before surgery to shrink the tumour (neoadjuvant therapy) or after surgery to destroy any remaining cancer cells (adjuvant therapy).
Radiation Therapy: High-energy X-rays or other types of radiation are used to kill cancer cells. It can be used alone or in combination with other treatments.
Targeted Therapy: These drugs specifically target certain genes or proteins that help cancer cells grow and spread, while minimising damage to healthy cells.
Immunotherapy: This treatment helps the body's own immune system fight the cancer.
Palliative Care: In advanced stages where a cure is not possible, treatment focuses on managing symptoms, improving quality of life, and providing support to the patient and their family.